In our previous paper, we predicted $sigma_{rm R}$ for $^{40-60,62,64}$Ca+ $^{12}$C scattering at 280 MeV/u, using the Kyushu (chiral) $g$-matrix folding model with the densities calculated with D1S-GHFB with and without the AMP. Interaction cross sections $sigma_{rm I}$ are available for $^{42-51}$Ca + $^{12}$C scattering, whereas $sigma_{rm R}$ are available for p+$^{48}$Ca scattering. As for $^{48}$Ca, the high-resolution $E1$ polarizability experiment ($E1$pE) yields $r_{rm skin}^{48}(E1{rm pE}) =0.14 sim 0.20~{rm fm}$. We determine $r_{rm skin}^{48}({rm exp})$ from the data on $sigma_{rm R}$ for p+$^{48}$Ca scattering and from the data on $sigma_{rm I}$ for $^{48}$Ca+$^{12}$C scattering. We use the chiral (Kyushu) $g$-matrix folding model with the densities calculated with the Gogny-D1M Hartree-Fock-Bogoliubov with the AMP. The D1M-GHFB+AMP proton and neutron densities are scaled so as to reproduce the data under the condition that the radius $r_{rm p}$ of the scaled proton density equals the data $r_{rm p}({rm exp})$ of the electron scattering. The neutron radius $r_{rm n}$ thus obtained is an experimental value. Our results are $r_{rm skin}^{48}({rm exp})=-0.031sim 0.183$fm for p+$^{48}$Ca and $0.100 sim 0.218$fm for $^{48}$Ca + $^{12}$C scattering. Using the $r_{rm skin}^{48}$-$r_{rm skin}^{208}$ relation with a high correlation coefficient $R=0.99$, we have transformed $r_{rm skin}^{208}({rm PREXII})$ and $r_{rm skin}^{208}(E1{rm pE})$ to the corresponding values $r_{rm skin}^{48}({rm tPREXII})$ and $r_{rm skin}^{48}({rm t}E1{rm pE})$. The transformed data $r_{rm skin}^{48}({rm tPREXII})=0.190 sim 0.268$fm is consistent with $r_{rm skin}^{48}=0.102 sim 0.218$fm for $^{48}$Ca + $^{12}$C. Our final result is $r_{rm skin}^{48}=0.102 sim 0.218$fm determined from $^{48}$Ca + $^{12}$C scattering.
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